1. Field of the Invention
This invention relates to hand tools for turning threaded machine nuts and bolts, and more particularly concerns a wrench for engaging nuts and bolts that are not easily accessible.
2. Description of the Prior Art
Numerous wrenches have earlier been disclosed for use on machine bolts that cannot be directly viewed by the mechanic or other person utilizing the wrench. Such devices are designed to grip a nut or the head of a machine bolt, said nut or head having a square or hexagonal shape. By virtue of specialized design features, such devices enable the mechanic to reach and turn nuts and bolts that would be otherwise inaccessible because of either tight quarters or obscured view.
U.S. Pat. No. 4,718,316, for example, discloses an attachment for a common wrench, said attachment having a magnetic head which facilitates the starting of nuts upon bolts positioned in a location inaccessible for both hands of the person using the wrench.
U.S. Pat. No. 4,406,188 discloses a nut-holding attachment for an open-end wrench with fixed jaws, and is designed to prevent the wrench from falling off a nut or bolt during tightening.
U.S. Pat. No. 4,901,608 discloses a ratchet wrench having a pivoted head which permits adjustability of the angle of the head relative to the handle of the wrench. Although such devices find specialized uses in certain specific applications, they lack versatility in coping with the general problem of manipulating inaccessible threaded members.
Various wrenches have been employed in attempts to specifically reach the nuts which engage the lower extremity of a sink faucet and are referred to as basin-cock wrenches. These wrenches typically have an elongated shaft having a lower extremity associated with a T-handle, and an upper extremity having pivotally associated paired spring loaded jaws. The jaws are manually spread and wrapped around the nut. When the shaft is turned, the jaws engage the nut and loosen or tighten it. There are several shortcomings of such a wrench. The jaws are not easily engaged with the nut, and slippage may occur, thereby damaging the nut. The jaws do not have enough gripping force to effect rotation of an extremely tight nut. Furthermore, in order to reverse direction of torque, the wrench must be removed and the jaws pivoted over the shaft, and then re-engaged with the nut.
Another type of wrench adapted to engage nuts and bolts of substantially inaccessible nature is commonly referred to as a crowfoot wrench. The crowfoot wrench consists of a flat open end wrench at one extremity and a square aperture at the opposite extremity. The square aperture is adapted to be engaged by a square drive ratchet wrench extension post. The crowfoot wrench requires the use of a rachet wrench and extender. Often there is not sufficient room to effect the arcing motion of the rachet wrench in tight spaces. Moreover, the crowfoot wrench is engaged with the extension post by inserting the square end through the aperture. Generally in order for the parts to interlock, the square extremity must completely penetrate the aperture with a portion extending beyond the wrench. This protruding post portion renders it impossible to position the crowfoot wrench flush against a flat surface.
It is accordingly an object of the present invention to provide a wrench adapted to engage and transmit rotational force upon a nut or bolt located in a location which is otherwise substantially inaccessible.
It is another object of the present invention to provide a wrench of the aforesaid nature which may be positioned flush to a flat surface.
It is a further object of this invention to provide a kit comprised of a wrench of the aforesaid nature and removable fittings adjustable to a plurality of nut and bolt sizes.
It is yet another object of this invention to provide a wrench of the aforesaid nature which is simple to use, of durable construction, and amenable to low cost manufacture.
These and other beneficial objects and advantages will be apparent from the following description.